Engine-governor.



No. 745,349. PATENTE'D DEG. l 1903.

E. M. HEWLETT ENGINE GOVERNOR. APPLICATION FILED my 31, 1901.

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No. 745,349. BATENTED DEC. 1, 1903,

E. M. HEWLETT.

ENGINE GOVERNOR.

APPLICATION FILED MAY 3}, 1901.

2 SHEETS-SHEET 2.

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Witnesses J Inventor 5 Edward MHewlett counterbalance varied.

. NITED STATES Patented December 1, 1903.

PATENT OFFICE.

EDWARD M. HEWLETT, OF SOHENECTADY, NEW YORK, ASSIGNOR TO GEN- ERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ENGINE-GOVERNOR.

SPECIFICATION forming part of Letters Patent N 0. 745,349, dated December 1, 1903.

Application filed May 31, 1901.

To all whont it may concern.-

Be it known that I, EDWARD M. HEWLETT, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Engine-Governors, of which the following is a specification.

This invention relates to steam-engine governors, the object being to more vperfectly control the engine speed under variable load.

The invention is of particular advantage in connection with engines driving dynamoelectric generators, though it may be employed in other cases where fine regulation is required. W

In carrying out the invention I provide a centrifugal governor controlling the enginevalve, the centripetal force of the governor being controlled by means of an adjustable counterbalance, the efiect of which maybe varied by means of an electric motor governed by a control-circuit. The counterbalance consists of a movable weight controlled by worm-gearing operated by the electric motor, which may be shifted to or from a fulcrum, the lever system carrying the weight being linked to the arms of the governor. I prefe-rably mount the controlling electric motor on the same bracket with the counterbalance, its weight forming part of the counterbalance and operating thereon through a train of worm-gearing, by which the weight may be shifted and the aggregate effect of the I preferably employ a series electric motor having a split fieldcircuit permitting reversal of the motor and provide also limiting. devices governed by the movable weight to automatically open the circuit when the weight reaches the end of its travel.

My invention therefore comprises a centrifu gal governor for a steam-engine controlled by an adjustable counterweight, the value of which may be varied by an electric motor operated by a control-circuit.

It comprises also an organization of this kind in which the operating-motor forms part of the counterweight. It comprises also other more specific features, the novelty of which Serial No. 62,624. No model.)

will be hereinafter described, and definitely indicated in the claims.

In the accompanying drawings,which illustrate the invention, Figure 1 is a side elevation of a steam-engine governor embodying my improvements. 7 the electric control system. Fig. 3 is a plan View of the counterbalance for the governor, and Fig. 4 is a view on a plane at right angles to that of Fig. 3.

- 1 represents an engine-valve connected by a link with the bell-crank lever 2, linked to a centrifugal-governor 3. Mounted on a hollow post surrounding the shaft on which the governor is mounted is a bracket 4, in which is pivoted a frame 5, on one side of which is mounted an electric motor 6 and on the other a yoke 7, in the arms of which is journaled a shaft 8, driven by worm-gearing 9 and operated by the motor 6. The shaft 8 may also be controlled by a hand-lever 10, a suitable 7o clutch 11 being provided to permit independent operation. The shaft 8 is threaded and engages-a movable weight 12, slotted. at one side and engaging a guide 13, secured to the yoke. I

As will beevident from Figs. 2 and 3 the motor and weight 12 are on opposite sides of the pivot which supports them, and by shifting the weight the counterbalancing efiect on the governor 3 may be varied. This variation is controlled by means of the motor, a control-circuit for which leads to any suitable point close to or distant from the engine. This circuit is shown in Fig. 2, in which 14 represents a control-switch cooperating with two contacts 15 15 connecting with the two sides ofa split field 16 of the motor 6. The armature 17 of this motor is connected in series relation to the middle point of the field, as indicated. The adjustable weight 12 carries a projection 18 in alinement with arms on two limit-switches 19 19 by which the circuit governing'the electric motor-may be opened automatically when the weight has reached the limit of its travel. Thus by clos- 5 ing the switch 14011 contact 15 the circuit is closed through the limit-switch 19 and the left side of the motor-field, thereby operating Fig. 2 is a diagram of 55 i it in a direction to shift the weight toward the left, in the diagram, and the motor will operate until the projection 18 strikes the projecting end of the limit-switch 19, when it opens the circuit, thus preventing damage to the apparatus.

By throwing the switch 14 to the contact 15* the motor reverses and an opposite direction of movement of the weight 12 is effected. Similarly when it reaches the end of its travel the limit-switch 19 will be opened, thus arresting the motor. The arm 18 is provided with two pins 18 18 (see Fig. 2,) one of which engages the projection on the limitswitch and opens the control'circuit. When a reverse motor movement occurs, the limitswitch is closed, the operating-arm being angular in shape, as indicated at 19 19 The shifting of the weight varies the centripetal eifect of the governor-arms, and thereby the speed of the engine, by its action on the valve 1. By mounting the motor 6 on the same bracket which supports the weight the powertransmitting gearing between the motor and the weight is much simplified and the apparatus rendered much more compact and reliable. In order to steady the movements of the counterweight and prevent sudden changes, I connect to one arm of the bellcrank lever 2 a piston operating in a dashpot 20.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is

1. The combination of a centrifugal governor, an adjustable counterbalance therefor, an electrically-operated motor mounted on the counterbalance arm to oppose by its weight the effect of the counterbalance, and means operated by the motor for varying the value of the counterbalance.

2. The combination with a centrifugal steam-engine governor, of a pivoted bracket, a movable counterweight on the bracket for varying the centripetal effect of the governor, an electric motor mounted on the brackets, said motor acting by its weight to counteract the influence of the counterweight, means operated by the motor for shifting the counterweight, and a control-circuit for the motor.

3. The combination with a centrifugal steam-engine governor, of a pivoted bracket, a movable counterweight for varying the centripetal effect of the governor, a counterbalancing electric motor mounted on said bracket on the opposite side of the pivot from the counterweight, means operated by the motor for varying the relative effects of the weights of the motor and the counterweight, and a control-circuit for said motor.

4. A steam-engine governor provided with a movable counterweight, an elecric motor controlling the same, a control-circuit for the motor, and limit-switchesfor automatically opening the motor-circuit in either direction of travel at the limits of traverse of the counterweight.

5. A steam-engine governor provided with a counterweight for varying its centripetal force, a frame on which it is mounted, and an electric motor for operating the counterweight connected thereto by worm-gearing, said motor being carried by the same frame which carries the counterweight.

6. A steam-engine governor provided with an adjustable counterweight, an electric motor controlling the same and opposing the effect of the counterweight, and a dash pot for slowing the movements of the governor.

7. The combination of a steam-engine governor with a counterbalance for varying its centripetal force, an electric motor for shifting the counterbalance, said motor being mounted on the same movable frame as the counterweight, a control-circuit for the m0- tor, and hand-operated means for shifting the counterweight.

In witness whereof I have hereunto set my hand this 27th day of May, 1901.

EDWARD M. HEWLETT.

WVitnesses:

BENJAMIN B. HULL, MARGARET E. WooLLEY. 

